Vulnerabilities > CVE-2020-2160 - Cross-Site Request Forgery (CSRF) vulnerability in Jenkins

047910
CVSS 8.8 - HIGH
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
HIGH
network
low complexity
jenkins
CWE-352
nessus
NVD
Published: 2020-03-25
Updated: 2023-10-25

Summary

Jenkins 2.227 and earlier, LTS 2.204.5 and earlier uses different representations of request URL paths, which allows attackers to craft URLs that allow bypassing CSRF protection of any target URL.

Vulnerable Configurations

Part Description Count
Application
Jenkins
1045

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • JSON Hijacking (aka JavaScript Hijacking)
    An attacker targets a system that uses JavaScript Object Notation (JSON) as a transport mechanism between the client and the server (common in Web 2.0 systems using AJAX) to steal possibly confidential information transmitted from the server back to the client inside the JSON object by taking advantage of the loophole in the browser's Same Origin Policy that does not prohibit JavaScript from one website to be included and executed in the context of another website. An attacker gets the victim to visit his or her malicious page that contains a script tag whose source points to the vulnerable system with a URL that requests a response from the server containing a JSON object with possibly confidential information. The malicious page also contains malicious code to capture the JSON object returned by the server before any other processing on it can take place, typically by overriding the JavaScript function used to create new objects. This hook allows the malicious code to get access to the creation of each object and transmit the possibly sensitive contents of the captured JSON object to the attackers' server. There is nothing in the browser's security model to prevent the attackers' malicious JavaScript code (originating from attacker's domain) to set up an environment (as described above) to intercept a JSON object response (coming from the vulnerable target system's domain), read its contents and transmit to the attackers' controlled site. The same origin policy protects the domain object model (DOM), but not the JSON.
  • Cross-Domain Search Timing
    An attacker initiates cross domain HTTP / GET requests and times the server responses. The timing of these responses may leak important information on what is happening on the server. Browser's same origin policy prevents the attacker from directly reading the server responses (in the absence of any other weaknesses), but does not prevent the attacker from timing the responses to requests that the attacker issued cross domain. For GET requests an attacker could for instance leverage the "img" tag in conjunction with "onload() / onerror()" javascript events. For the POST requests, an attacker could leverage the "iframe" element and leverage the "onload()" event. There is nothing in the current browser security model that prevents an attacker to use these methods to time responses to the attackers' cross domain requests. The timing for these responses leaks information. For instance, if a victim has an active session with their online e-mail account, an attacker could issue search requests in the victim's mailbox. While the attacker is not able to view the responses, based on the timings of the responses, the attacker could ask yes / no questions as to the content of victim's e-mails, who the victim e-mailed, when, etc. This is but one example; There are other scenarios where an attacker could infer potentially sensitive information from cross domain requests by timing the responses while asking the right questions that leak information.
  • Cross Site Identification
    An attacker harvests identifying information about a victim via an active session that the victim's browser has with a social networking site. A victim may have the social networking site open in one tab or perhaps is simply using the "remember me" feature to keep his or her session with the social networking site active. An attacker induces a payload to execute in the victim's browser that transparently to the victim initiates a request to the social networking site (e.g., via available social network site APIs) to retrieve identifying information about a victim. While some of this information may be public, the attacker is able to harvest this information in context and may use it for further attacks on the user (e.g., spear phishing). In one example of an attack, an attacker may post a malicious posting that contains an image with an embedded link. The link actually requests identifying information from the social networking site. A victim who views the malicious posting in his or her browser will have sent identifying information to the attacker, as long as the victim had an active session with the social networking site. There are many other ways in which the attacker may get the payload to execute in the victim's browser mainly by finding a way to hide it in some reputable site that the victim visits. The attacker could also send the link to the victim in an e-mail and trick the victim into clicking on the link. This attack is basically a cross site request forgery attack with two main differences. First, there is no action that is performed on behalf of the user aside from harvesting information. So standard CSRF protection may not work in this situation. Second, what is important in this attack pattern is the nature of the data being harvested, which is identifying information that can be obtained and used in context. This real time harvesting of identifying information can be used as a prelude for launching real time targeted social engineering attacks on the victim.
  • Cross Site Request Forgery (aka Session Riding)
    An attacker crafts malicious web links and distributes them (via web pages, email, etc.), typically in a targeted manner, hoping to induce users to click on the link and execute the malicious action against some third-party application. If successful, the action embedded in the malicious link will be processed and accepted by the targeted application with the users' privilege level. This type of attack leverages the persistence and implicit trust placed in user session cookies by many web applications today. In such an architecture, once the user authenticates to an application and a session cookie is created on the user's system, all following transactions for that session are authenticated using that cookie including potential actions initiated by an attacker and simply "riding" the existing session cookie.

Nessus

  • NASL familyFreeBSD Local Security Checks
    NASL idFREEBSD_PKG_5BF6ED6D90024F43AD63458F59E45384.NASL
    descriptionJenkins Security Advisory : Description(High) SECURITY-1774 / CVE-2020-2160 CSRF protection for any URL could be bypassed (Medium) SECURITY-1781 / CVE-2020-2161 Stored XSS vulnerability in label expression validation (Medium) SECURITY-1793 / CVE-2020-2162 Stored XSS vulnerability in file parameters (Medium) SECURITY-1796 / CVE-2020-2163 Stored XSS vulnerability in list view column headers
    last seen2020-04-03
    modified2020-03-26
    plugin id134922
    published2020-03-26
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/134922
    titleFreeBSD : jenkins -- multiple vulnerabilities (5bf6ed6d-9002-4f43-ad63-458f59e45384)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from the FreeBSD VuXML database :
#
# Copyright 2003-2020 Jacques Vidrine and contributors
#
# Redistribution and use in source (VuXML) and 'compiled' forms (SGML,
# HTML, PDF, PostScript, RTF and so forth) with or without modification,
# are permitted provided that the following conditions are met:
# 1. Redistributions of source code (VuXML) must retain the above
#    copyright notice, this list of conditions and the following
#    disclaimer as the first lines of this file unmodified.
# 2. Redistributions in compiled form (transformed to other DTDs,
#    published online in any format, converted to PDF, PostScript,
#    RTF and other formats) must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer
#    in the documentation and/or other materials provided with the
#    distribution.
# 
# THIS DOCUMENTATION IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
# OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
# OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
# BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
# OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION,
# EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#

include("compat.inc");

if (description)
{
  script_id(134922);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/04/02");

  script_cve_id("CVE-2020-2160", "CVE-2020-2161", "CVE-2020-2162", "CVE-2020-2163");

  script_name(english:"FreeBSD : jenkins -- multiple vulnerabilities (5bf6ed6d-9002-4f43-ad63-458f59e45384)");
  script_summary(english:"Checks for updated packages in pkg_info output");

  script_set_attribute(
    attribute:"synopsis", 
    value:
"The remote FreeBSD host is missing one or more security-related
updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Jenkins Security Advisory : Description(High) SECURITY-1774 /
CVE-2020-2160 CSRF protection for any URL could be bypassed (Medium)
SECURITY-1781 / CVE-2020-2161 Stored XSS vulnerability in label
expression validation (Medium) SECURITY-1793 / CVE-2020-2162 Stored
XSS vulnerability in file parameters (Medium) SECURITY-1796 /
CVE-2020-2163 Stored XSS vulnerability in list view column headers"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://jenkins.io/security/advisory/2020-03-25/"
  );
  # https://vuxml.freebsd.org/freebsd/5bf6ed6d-9002-4f43-ad63-458f59e45384.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?be2bbc7a"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2020-2160");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:jenkins");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:jenkins-lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/03/25");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/03/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/03/26");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"FreeBSD Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/FreeBSD/release", "Host/FreeBSD/pkg_info");

  exit(0);
}


include("audit.inc");
include("freebsd_package.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/FreeBSD/release")) audit(AUDIT_OS_NOT, "FreeBSD");
if (!get_kb_item("Host/FreeBSD/pkg_info")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;

if (pkg_test(save_report:TRUE, pkg:"jenkins<=2.227")) flag++;
if (pkg_test(save_report:TRUE, pkg:"jenkins-lts<=2.204.5")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:pkg_report_get());
  else security_warning(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");
  • NASL familyCGI abuses
    NASL idJENKINS_SECURITY_ADVISORY_2020-03-25.NASL
    descriptionThe version of Jenkins running on the remote web server is prior to 2.228 or is a version of Jenkins LTS prior to 2.204.6 or 2.222.1. It is, therefore, affected by multiple vulnerabilities: - An authentication bypass vulnerability exists in Jenkins
    last seen2020-04-07
    modified2020-04-02
    plugin id135178
    published2020-04-02
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/135178
    titleJenkins < (2.204.6 / 2.222.1) LTS / 2.228 Multiple Vulnerabilities
    code
    #
# (C) Tenable Network Security, Inc.
#

include('compat.inc');

if (description)
{
  script_id(135178);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/07/24");

  script_cve_id(
    "CVE-2020-2160",
    "CVE-2020-2161",
    "CVE-2020-2162",
    "CVE-2020-2163"
  );
  script_xref(name:"IAVA", value:"2020-A-0126-S");

  script_name(english:"Jenkins < (2.204.6 / 2.222.1) LTS / 2.228 Multiple Vulnerabilities");

  script_set_attribute(attribute:"synopsis", value:
"A job scheduling and management system hosted on the remote web server is affected by multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"The version of Jenkins running on the remote web server is prior to 2.228 or is a version of Jenkins LTS prior to 
2.204.6 or 2.222.1. It is, therefore, affected by multiple vulnerabilities:

  - An authentication bypass vulnerability exists in Jenkins' CSRF prevention component. An unauthenticated, remote 
    attacker can exploit this, by sending specially crafted requests to a vulnerable Jenkins instance, to bypass 
    authentication and conduct a CSRF attack (CVE-2020-2160).

  - A stored cross-site scripting (XSS) vulnerability exists in Jenkins' label expression validation component due to 
    improper validation of user-supplied input before returning it to users. An authenticated, remote attacker can 
    exploit this, by convincing a user to click a specially crafted URL, to execute arbitrary script code in a user's 
    browser session (CVE-2020-2161).

  - A stored cross-site scripting (XSS) vulnerability exists in Jenkins' file parameter component due to improper 
    validation of user-supplied input before returning it to users. An authenticated, remote attacker can exploit this,
    by convincing a user to click a specially crafted URL, to execute arbitrary script code in a user's browser 
    session (CVE-2020-2162).

  Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
  number.");
  # https://jenkins.io/security/advisory/2020-03-25/
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?edd15de3");
  script_set_attribute(attribute:"solution", value:
"Upgrade Jenkins to version 2.228 or later. Upgrade Jenkins LTS to version 2.204.6, 2.222.1 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2020-2160");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/03/25");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/03/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/04/02");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:cloudbees:jenkins");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"CGI abuses");
  script_copyright(english:"This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("jenkins_detect.nasl");
  script_require_keys("www/Jenkins");
  script_require_ports("Services/www", 8080);

  exit(0);
}

include('http.inc');
include('vcf.inc');

port = get_http_port(default:8080);
app = vcf::get_app_info(app:'Jenkins', webapp:TRUE, port:port);
fixed_display = '2.204.6 or 2.222.1 LTS / 2.228';

if(app['LTS'])
  constraints = [{'fixed_version' : '2.204.6', 'fixed_display' : fixed_display}];
else # Weekly
  constraints = [{'fixed_version' : '2.228', 'fixed_display' : fixed_display}];

vcf::check_version_and_report(
  app_info:app,
  constraints:constraints,
  severity:SECURITY_WARNING,
  strict:FALSE
);

References